Transcript for Families return to their homes to find no power or water in 90 degree weather

In the meantime tonight, all across this storm zone, people who fled the storm are now returning home to assess the damage and try to get on with their lives, to rebuild. But millions of those homes still have no electricity and in so many cases, no water. And making it worse, temperatures holding near 90 all across this state. ABC's chief national correspondent Tom llamas near ft. Myers again tonight. Reporter: Today, outside of Miami beach, an epic traffic jam. Residents who evacuated for Irma now finally allowed to return. But for so many coming home, it's just the beginning. More than 4 million customers still without power. Bracing for another night in the dark. No power. Over 24 hours now. Reporter: Here in ft. Myers, Dave and Margie take me inside their home. It's complete darkness. When I lose the flashlig -- that's what it's like for a lot of people here in Florida. No ac, no running water, either. They got the tub filled up here. People use this water to bathe, they use this water to drink. Whatever it takes to get by. Repair crews from 30 states and Canada. Coming down. Reporter: Now joining the teams already in Florida. It's intense, but we just take it step by step, one job at a time. Reporter: But restoring electricity to the whole state could take weeks. The power outages also leading to traffic in some cases. With the traffic lights out at this intersection, cars H to treat it like a four-way stop. And that's leading to some backups, as you can see. Clogs the roads as far as the eye can see. Today, some drivers ignoring those rules. The Sarasota sheriff's department reporting multiple crashes. The greatest number of fatalities when it comes to a storm like this occurs after the storm has passed. Reporter: In Lee county, at least 21 people hospitalized with possible carbon monoxide poisoning. There was a generator running at that resident when they did call. They were instructed to turn it off. Reporter: Authorities spreading the word -- if you have a generator, you must keep it outside. David, just behind me, you can see what some of these utility crews are up against. Entire neighborhoods flooded out. But believe it or not, some of the people in this neighborhood do have their power back. They have restored power to more than 2 million customers. David? Tom llamas with us again

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